Method and system for providing docking guidance to a pilot of a taxiing aircraft

ABSTRACT

Apparatus and associated methods relate to using an image of a fiducial located indicating a parking location for the aircraft to provide docking guidance data to a pilot of an aircraft. The fiducial has vertically-separated indicia and laterally-separated indicia. A camera is configured to mount at a camera location so as to be able to capture two-dimensional images of a scene external to the aircraft. The two-dimensional image includes pixel data generated by the two-dimensional array of light-sensitive pixels. A digital processor identifies first and second sets of pixel coordinates corresponding to the two vertically-separated and the two laterally-separated indicia, respectively. The digital processor then calculates, based at least in part on the identified first pixel coordinates corresponding to the two vertically-separated indicia, a range to the parking location.

BACKGROUND

Each year, significant time and money are lost due to commercialaircraft accidents and incidents during ground operations, of whichsignificant portions occur during taxiing maneuvers. During groundoperations, aircraft share the taxiways with other aircraft, fuelvehicles, baggage carrying trains, mobile stairways and many otherobjects. Aircrafts often taxi to and/or from fixed buildings and otherfixed objects. Should an aircraft collide with any of these objects, theaircraft must be repaired and recertified as capable of operation. Thecost of repair and recertification, as well as the lost opportunitycosts associated with the aircraft being unavailable for use can be veryexpensive.

Pilots are located in a central cockpit where they are well positionedto observe objects that are directly in front of the cabin of theaircraft. Wings extend laterally from the cabin in both directions. Somecommercial and some military aircraft have large wingspans, and so thewings on these aircraft laterally extend a great distance from the cabinand are thus positioned behind and out of the field of view of thecabin. Some commercial and some military planes have engines that hangbelow the wings of the aircraft. Pilots, positioned in the cabin, canhave difficulty knowing the risk of collisions between the wingtipsand/or engines and other objects external to the aircraft. An aircraftoptical guidance docking system would be useful to help a pilot alignthe aircraft with a parking location at a gate passenger boardingbridge, and to survey the area forward of the tail, wingtips and/orengines, to detect obstructions in a potential collision path, and toprovide visual and audible alerts to the cockpit.

SUMMARY

Apparatus and associated devices relate to providing guidance to a pilotof a taxiing aircraft. The provided guidance includes providingalignment metrics indicative of an alignment of the taxiing aircraft toa parking location identified by an alignment fiducial. In someembodiments the provided guidance includes obstacle metrics indicativeof range and/or location of obstacles within a path of the taxiingaircraft. An optical docking guidance system includes a camera and adigital processor. The camera is configured to mount at a cameralocation on an aircraft so as to generate a two-dimensional image of ascene external to the taxiing aircraft. The scene is aligned with anoptical axis of the camera. The two-dimensional image includes opticalintensity data for each of a two-dimensional array of pixels. Each pixelhas a pixel coordinate representing a location of the pixel within thetwo-dimensional array. The digital processor is configured to identifyfirst and second sets of pixel coordinates within the image of the sceneexternal to the aircraft. The identified first and second sets of pixelcoordinates corresponding to two vertically-separated and twolaterally-separated indicia, respectively, of an alignment fiducialindicating the parking location for the taxiing aircraft. The digitalprocessor is further configured to calculate, based at least in part onthe identified first pixel coordinates corresponding to the twovertically-separated indicia, a range to the parking location.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an airport with two aircraft parked atgate locations.

FIG. 2 is a block diagram of an exemplary aircraft collision alertingsystem.

FIG. 3 is a schematic view of an aircraft using an exemplary opticaldocking guidance system to align the aircraft with stand positionmarking.

FIG. 4 is an exemplary fiducial as imaged by a camera from an aircraftat various alignments and positions relative to the fiducial.

FIG. 5 is a block diagram of method for calculating alignment metricsfor use in optical guidance of aircraft docking.

FIG. 6 is a schematic view of an aircraft using an exemplary opticaldocking guidance system having two fiducials.

DETAILED DESCRIPTION

Apparatus and associated methods relate to using an image of a fiducialindicating a parking location for the aircraft to provide dockingguidance data to a pilot of an aircraft. The fiducial hasvertically-separated indicia and laterally-separated indicia. A camerais configured for mounting at a camera location so as to be able tocapture two-dimensional images of a scene external to the aircraft. Thetwo-dimensional image includes pixel data generated by thetwo-dimensional array of light-sensitive pixels. A digital processoridentifies first and second sets of pixel coordinates corresponding tothe two vertically-separated and the two laterally-separated indicia,respectively. The digital processor then calculates, based at least inpart on the identified first pixel coordinates corresponding to the twovertically-separated indicia, a range to the parking location.

FIG. 1 is a schematic view of an airport with two aircraft at gatelocations. In FIG. 1, airport concourse 10 includes gate passengerboarding bridges 12 and 14 for parked aircraft 16 and taxiing aircraft18, respectively. Aircraft stand position markers 20 and 22 are paintedon tarmac 24 so as to provide visual alignment indicators to the pilotstaxiing aircrafts 16 and 18 to gate passenger boarding bridges 12 and14, respectively. Aircraft stand position markers 20 and 22 eachincludes two portions: i) stand lead-in lines 26 and 28; and ii) stoplines 30 and 32, respectively. Each of stand lead-in lines 26 and 28provides a visible line of direction for aircrafts 16 and 18 to followwhile taxiing to gate passenger boarding bridges 12 and 14,respectively. Each of stop lines 30 and 32 provides a visible indicatorof a desired location of forward landing gear when aircraft 16 and 18are parked at gate passenger boarding bridges 12 and 14, respectively.

Aircraft 16 is parked at gate passenger boarding bridge 12, which hasbeen positioned to provide a walkway for passengers embarking and/ordisembarking aircraft 16. Aircraft 16 has been parked at gate passengerboarding bridge 12 in such a way that aircraft 16 is misaligned withaircraft stand position marker 20. Aircraft 16 is parked such thatlongitudinal axis 34 of aircraft 16 is to the left of stand lead-in line26. Because aircraft 16 is parked to the left of stand lead-in line 26,aircraft 16 is encroaching upon the space reserved proximate gatepassenger boarding bridge 14 toward which aircraft 18 is taxiing.Although longitudinal axis 36 of taxiing aircraft 18 is aligned withstand lead-in line 28, taxiing aircraft 18 encounters two collisionhazards as aircraft 18 taxis toward gate passenger boarding bridge 14.First, wingtip 38 of aircraft 16 is obstructing wingtip 40 of taxiingaircraft 18. Second, gate passenger boarding bridge 14 is positioned soas to obstruct nacelle 42 of taxiing aircraft 18.

Taxiing aircraft 18 is equipped with a camera located on verticalstabilizer 44 for providing optical docking guidance. The camera locatedon vertical stabilizer 44 has an optical axis aligned with longitudinalaxis 36 of aircraft 18. The camera located on vertical stabilizer 44 hasfield of view 46 as indicated in the figure. The camera located onvertical stabilizer 44 is part of an optical docking guidance system. Insome embodiments, the optical docking guidance system can be used toassist the pilot in aligning the aircraft with the intended parkinglocation indicated by aircraft stand position markers 22. In someembodiments, the optical docking guidance system can also be used todetect potential collisions and to provide an alert signal to the pilotwhen a risk of collision exceeds a predetermined risk threshold.

In some embodiments, an optical docking guidance system can also providea collision alert capability. For example, the optical docking guidancesystem of taxiing aircraft 18 includes a light projector mounted at aprojector location on the left wing 48 of taxiing aircraft 18. The lightprojector is configured to project a structured image onto a sceneexternal to taxiing aircraft 18, thereby illuminating objects nearby andexternal to taxiing aircraft 18. The light projector and/or camera canbe mounted at various locations on taxiing aircraft 18. Some examples ofsuch collision alerting capabilities are disclosed by Ell et al. in U.S.patent application Ser. No. 15/385,224, filed Dec. 20, 2016, titled“Method and System for Aircraft Taxi Strike Alerting,” the entiredisclosure of which is hereby incorporated by reference.

The structured image that is projected by the light projector hasfeatures that can be identified in images formed by the camera mountedat the camera location on vertical stabilizer 44. Location(s) andrange(s) of object(s) imaged by the camera can be calculated usingtriangulation. Such calculations are based on the projector location,the camera location, and the location within the generated image (e.g.,pixel coordinates) where the structured light reflected by objects inthe scene. For example, the light projector can be located at aprojector location on taxiing aircraft 18 that is different from acamera location where the camera is located. The pixel coordinatescorresponding to the structured-light portions of the generated imagecan be used to determine a location(s) and a range(s) of object(s) fromwhich that structured light is reflected.

The light projector, for example, can project a structured image thatincludes a pattern of lines projecting at various angles of elevationfrom the light projector. One line might be projected at an angle ofelevation of zero degrees (i.e., directed parallel to the horizon). Asecond line might be projected at an angle of negative five degrees fromthe horizon (i.e., directed at a slightly downward angle from the lightprojector). Each of these projected lines of light, when reflected froman object, will be imaged at different regions (e.g., each will have adifferent vertical pixel coordinate) within the camera image, dependingon the range distance between the reflecting object and taxiing aircraft18. Knowing the projector location of the light projector, the cameralocation of the camera, the specific feature of the structured image(e.g., which horizontal line is imaged), and the pixel coordinateswithin the generated image corresponding to the specific feature canpermit a determination of the location(s) and/or range(s) of theobject(s) from which the specific feature has been reflected.

The light projector projects the spatially-patterned light over a solidangle of illumination. The projected spatially-patterned lightilluminates objects that reside within the solid angle of illumination.In the depicted embodiment, the light projector has an optical axis thatis coplanar with longitudinal axis 36 of taxiing aircraft 18. The lightprojector illuminates objects that are within an azimuthal range of+/−85 degrees, for example, of longitudinal axis 36 of taxiing aircraft18, and within an elevation range of a projection horizon of the lightprojector. The elevation range of projection, for example, can be fromabout +3, +5, +10, +12, or +15 degrees to about −2, −5, −8, or −10degrees of projection from a vertical location of the light projector,sufficient to encompass the wingtips of both left and right wings, aswell as a plane extending forward of these wingtips parallel tolongitudinal axis 36 of taxiing aircraft 18.

The spatially patterned light can have a wavelength corresponding toinfrared light and/or to an atmospheric absorption band. Using infraredlight can minimize a distraction to a pilot who is taxiing the aircraft.Using infrared light that is of lower solar intensity can permitlow-power projector illumination, as the illuminating power need notcompete with the sun's illumination in some spectral bands. Projectorsusing IR spectrum that has solar illumination absorbed by the atmospherecan further reduce the required illumination. Knowing a first aircraftlocation from where the light is projected, a second aircraft locationwhere the reflection is imaged, and a location within the imagecorresponding to a feature of the spatially patterned light permits acalculation of the location and range of the illuminated object.

Using the calculated location information, pilots taxiing aircraft 18can be informed of any potential collision hazards within the sceneilluminated by the light projector. Pilots of taxiing aircraft 18 cancease forward progress of aircraft 18 or steer aircraft 18 to avoidwingtip collisions and/or engine nacelle collisions based on thelocation(s) and range(s) of object(s) (e.g., passenger boarding bridgegate 14 and wingtip 38 of parked aircraft 16) that is calculated by suchan aircraft collision alerting system.

FIG. 2 is a block diagram of an exemplary optical docking guidancesystem. Optical docking guidance system 50 includes infraredprojector(s) 52, camera(s) 54, digital processor 56, and cockpit alarmand display module 58. Infrared projector(s) 52 is configured to bemounted at a projector location(s) on an aircraft. Infrared projector(s)52 is further configured to project spatially-patterned light frominfrared projector(s) 52 onto a scene external to the aircraft, therebyilluminating a spatially-patterned portion of the scene.

Camera(s) 54 is configured to be mounted at one or more camera locationson the aircraft. Camera(s) 54 is further configured to receive lightreflected from the scene. Camera(s) 54 is further configured to focusthe received light onto a focal plane array comprising a plurality oflight-sensitive pixels, thereby forming an image of the scene. The imagecan include pixel data generated by the plurality of light-sensitivepixels.

Digital processor 56 receives inputs from camera(s) 54 and from aircraftavionics 60. Digital processor 56 generates commands that control theoperation of infrared projector(s) 52 and camera(s) 54. Digitalprocessor 56 outputs alarms ranges and images to cockpit alarms anddisplay module 58. Digital processor 56 is configured to identify pixelcoordinates corresponding to a subset of the plurality oflight-sensitive pixels upon which the spatially-patterned lightprojected by infrared projector(s) 52 and reflected from thespatially-patterned portion of the scene is focused. Digital processor56 is further configured to use triangulation, based on the projectorlocation of infrared projector(s) 52, the location(s) of camera(s) 54and the identified pixel coordinates, to calculate range value data ofobject(s) in the scene from which the spatially-patterned lightprojected by infrared projector(s) 52 is reflected. Digital processor 56can be configured to execute as an image processor.

FIG. 3 is a schematic view of an aircraft using an exemplary opticaldocking guidance system to align the aircraft with stand positionmarking. In FIG. 3, taxiing aircraft 18 is approaching a parkinglocation indicated by aircraft stand position marker 22. Aircraft 18 isequipped with an optical docking guidance system. The optical dockingguidance system uses alignment fiducial 62 to provide a visualindication of the parking location. Alignment fiducial 62 is laterallyaligned along stand lead-in line 28, thereby providing a visualindicator of the parking location.

Alignment fiducial 62 has at least two vertically-separated indicia andat least two laterally-separated indicia. In the depicted embodiment,alignment fiducial 62 includes a circle that has four quadrants.Alternating quadrants of the circle are alternately shaded. Variousfeatures of alignment fiducial 62 can be used as laterally-separatedand/or vertically-separated indicia. For example, laterally-separatedindicia 64 and 66 are located on the lateral sides of the circle wherethe top and bottom quadrants abut one another. Vertically-separatedindicia 68 and 70 are located on the vertical sides of the circle wherethe left and right quadrants abut one another.

When alignment fiducial 62 is in the field of view of camera(s) 54 ofoptical docking guidance system 50, the generated image will includeimage features depicting alignment fiducial 62. The portion of thegenerated image corresponding to alignment fiducial 62 containsinformation regarding the relative alignment of taxiing aircraft 18 withthe parking location indicated by aircraft stand position marker 22. Forexample, as taxiing aircraft 18 approaches alignment fiducial 62, theportion of the generated image corresponding to alignment fiducial 62increases in size. Also, if longitudinal axis 36 of taxiing aircraft 18is parallel to but laterally translated from stand lead-in line 28, theportion of the generated image corresponding to alignment fiducial 62will be translated from a centerline of the generated image. If,however, longitudinal axis 38 of taxiing aircraft 18 is at an angle θwith respect to stand lead-in line 28, then the portion of the generatedimage corresponding to alignment fiducial 62 will be distorted (e.g.,the lateral pixel dimension of the circle will differ from the verticalpixel dimension of the circle). Thus, the pixel coordinatescorresponding to the vertically-separated 68 and 70 andlaterally-separated 64 and 66 indicia can be used to calculate a rangeR, a lateral translation A_(L) and an alignment angle θ characterizingthe alignment of taxiing aircraft 18 to the parking location indicatedby aircraft stand position marker 22.

In some embodiments, alignment fiducial 62 is a standard size and isconfigured to be located at a standard distance from stop line 32. Insome embodiments, alignment fiducial 62 can be sized so that whenlocated at whatever distance it is located from stop line 32, alignmentfiducial 62 will be imaged at a standard image size by camera(s) 54.

Infrared projector(s) 52 can generate a light pattern, akin to afiducial pattern, on surfaces of airport concourse 10 to estimatedistance and/or angle, when alignment fiducial 62 is not available orpresent. There are restrictions in the locations of light projector 52and camera 54 on taxiing aircraft 18 so as to permit measurement ofdistance and/or angle of taxiing aircraft 18 with respect to the parkinglocation. There are limitations, however, in what the system can computeusing only a projected fiducial. A digital processor might not be ableto determine the offset from the centerline without the alignmentfiducial 62 or some other additional data for the location of thecenterline.

FIG. 4 is an exemplary fiducial as imaged by a camera from an aircraftat various alignments and positions relative to the fiducial. In FIG. 4.Images 72 and 72A-I are various images of alignment fiducial 62generated by camera(s) 54 attached to taxiing aircraft 18 at variousalignment configurations with respect to alignment fiducial 62. Image 72represents the image generated by camera(s) 54 when aircraft 18 isperfectly aligned with the parking position indicated by aircraft standposition marker 22. Images 72A-D represent the images generated bycamera(s) 54 when aircraft 18 is at the proper distance from alignmentfiducial 62, but longitudinal axis 36 of aircraft 18 is not parallel toaircraft stand position marker 22.

Images 72A and 72C are generated by camera(s) 54 when longitudinal axis36 of aircraft 18 has an alignment angle θ that is less than 0°. Images72B and 72E are generated by camera(s) 54 when longitudinal axis 36 ofaircraft 18 has an alignment angle θ that is greater than 0°. Images 72Aand 72B correspond to alignment scenarios in which a magnitude of thealignment angle θ is smaller than alignment scenarios corresponding toimages 72C and 72D. In other words, images 72A and 72B are indicative ofa rotational misalignment, which is not as grievous as the rotationalmisalignment indicated by images 72C and 72D.

The pixel coordinates corresponding to the vertically-separated 68 and70 and laterally-separated 64 and 66 indicia can be used to calculatethe angle between longitudinal axis 36 of aircraft 18 and stand lead-inline 28. For example, a difference between the pixel coordinatescorresponding to the laterally-separated indicia 64 and 66 can provide alateral measure of the imaged separation of the laterally-separatedindicia 64 and 66. A difference between the pixel coordinatescorresponding to the vertically-separated indicia 68 and 70 can providea vertical measure of the imaged separation of the vertically-separatedindicia 68 and 70. A ratio of the lateral measure to the verticalmeasure is indicative of the alignment angle θ of longitudinal axis 36of taxiing aircraft 18 with respect to stand lead-in line 28.

Images 72E-72I are generated by camera(s) 54 when taxiing aircraft 18 isapproaching but has not yet reached the parking location indicated byaircraft stand position marker 22. In images 72E-72I, the sizes of theimages are smaller than the size of target image 72. Images 72E-Gcorrespond to alignment scenarios in which the range R of taxiingaircraft 18 is greater than zero (e.g., taxiing aircraft 18 has not yetreached the parking location indicated by stop line 32). Also, images72H and 72I correspond to alignment scenarios in which the range R oftaxiing aircraft 18 is greater than the range of taxiing aircraft 18when capturing images 72E-G.

The pixel coordinates corresponding to the vertically-separated indicia68 and 70 can be used to calculate the range of aircraft 18 and theparking location indicated by aircraft stand position marker 22. Forexample, a difference between the pixel coordinates corresponding to thevertically-separated indicia 68 and 70 can provide a vertical measure ofthe imaged separation of the vertically-separated indicia 68 and 70. Aratio of the vertical measure to a predetermined standard verticalmeasure is indicative of the range R aircraft 18 and the parkinglocation indicated by aircraft stand position marker 22.

The lateral translation of longitudinal axis 36 of aircraft 18 withrespect to aircraft stand position marker 28 can also be calculatedusing pixel coordinates. If longitudinal axis 36 of aircraft 18 isparallel to but laterally translated from stand lead-in line 28, then adifference between the pixel coordinates corresponding tovertically-separated indicia 68 and 70, and a coordinates of a verticalcenter line of the generated image is indicative of lateral translationA_(L). If longitudinal axis 36 of aircraft 18 is both translated and notparallel to stand lead-in line 28, then a combination of the lateraltranslation and alignment angle can be calculated using various imagetranslation algorithms (e.g., affine scale-invariant featuretranslation).

FIG. 5 is a block diagram of method for calculating alignment metricsfor use in optical guidance of aircraft docking. In FIG. 5, alignmentmetric calculation method 74 includes predetermined reference image 76,live image 78 captured by camera(s) 54 and image processor 80. Imageprocessor 80 receives both predetermined reference image 76 and liveimage 78 as inputs. In some embodiments, image processor identifiesportions of live image 78 corresponding to alignment fiducial 62. Imageprocessor may then determine pixel locations for vertically-separated 68and 70 and/or laterally-separated 64 and 66 indicia of alignmentfiducial 62. Image processor 80 may then calculate, based on thedetermined pixel coordinates, alignment metrics (e.g., range R and/oralignment angle θ, and/or translation A_(L)). Image processor 80 can useone or more of various algorithms to compute the desired output data.For example, one such algorithm is the affine scale-invariant featuretranslation algorithm. In some embodiments, the above disclosed imageprocessing functions can be performed by image processor 80 and/or bydigital processor 56.

FIG. 6 is a schematic view of an aircraft using an exemplary opticaldocking guidance system having two fiducials. In FIG. 6, taxiingaircraft 18 is approaching a parking location indicated by aircraftstand position marker 22. Aircraft 18 is equipped with an opticaldocking guidance system. In this embodiment, the optical dockingguidance system uses two alignment fiducials 62L and 62R to providevisual indication of the parking location indicated by aircraft standposition marker 22. Alignment fiducials 62L and 62R are laterallyaligned apart from one another. Alignment fiducials 62L and 62R arelaterally spaced equidistant, for example, from stand lead-in line 28,thereby providing a visual indication of the parking location.

The optical docking guidance system used in conjunction with twoalignment fiducials, such as is depicted in FIG. 6, may have two cameras54, mounted at camera locations on each of wings 48 and 49. In someembodiments, image projector 52 is located at a projector location onvertical stabilizer 44. Alignment fiducial 62R is configured to belocated within a field of view of the one of camera(s) 54 mounted onright aircraft wing 49. Alignment fiducial 62L is configured to belocated within a field of view of the other one of cameras 54 mounted onleft aircraft wing 48.

The following are non-exclusive descriptions of possible embodiments ofthe present invention.

Apparatus and associated methods relate to a system for providingdocking guidance to a pilot of a taxiing aircraft. The system includes acamera configured to be mounted at a camera location on the taxiingaircraft. The camera is configured to generate a two-dimensional imageof a scene external to the taxiing aircraft. The generatedtwo-dimensional image includes pixel data generated by thetwo-dimensional array of light-sensitive pixels. The system includes adigital processor configured to identify first and second sets of pixelcoordinates within the generated two-dimensional image of the sceneexternal to the taxiing aircraft. The identified first and second setsof pixel coordinates correspond to two vertically-separated and twolaterally-separated indicia, respectively, of an alignment fiducialindicating a parking location for the taxiing aircraft. The digitalprocessor is further configured to calculate, based at least in part onthe identified first pixel coordinates corresponding to the twovertically-separated indicia, a range to the parking location indicatedby the alignment fiducial.

The system of the preceding paragraph can optionally include,additionally and/or alternatively, any one or more of the followingfeatures, configurations and/or additional components:

A further embodiment of the foregoing system can further include acockpit notification system configured to provide a visual display ofthe generated image of the scene aligned with the optical axis of thecamera. The provided visual display can be annotated with the calculatedrange to the parking location.

A further embodiment of any of the foregoing systems, wherein thedigital processor can be further configured to calculate, based at leastin part on the identified second pixel coordinates corresponding to thetwo laterally-separated indicia, an angle of the taxiing aircraft withrespect to a normal vector of the alignment fiducial.

A further embodiment of any of the foregoing systems, wherein thedigital processor can be further configured to calculate, based at leastin part on the identified second pixel coordinates corresponding to thetwo laterally-separated indicia, a lateral translation of thelongitudinal axis of the taxiing aircraft with respect to the parkinglocation identified by the alignment fiducial.

A further embodiment of any of the foregoing systems can further includea light projector configured to be mounted at a projector location onthe taxiing aircraft and to project spatially-patterned light from thelight projector onto the scene external to the taxiing aircraft, therebyproviding illumination of a spatially-patterned portion of the sceneexternal to the taxiing aircraft. The digital processor can be furtherconfigured to identify a third set of pixel coordinates within the imageof the scene external to the taxiing aircraft. The identified third setof pixel coordinates corresponds to the spatially-patterned portion ofthe scene. The digital processor can be further configured to usetriangulation, based on the projector location of the light projector,the camera location of the camera and the identified third set of pixelcoordinates, to calculate location(s) and/or range(s) of object(s) inthe scene external to the taxiing aircraft from which thespatially-patterned light projected by the light projector is reflected.

A further embodiment of any of the foregoing systems, wherein thespatially-patterned light projected by the light projector can includeinfrared light.

A further embodiment of any of the foregoing systems, wherein the camerais an infrared camera and the light-sensitive pixels are sensitive toinfrared light.

A further embodiment of any of the foregoing systems can further includea cockpit notification system configured to generate a visual display ofthe image aligned with the optical axis of the camera annotated with thecalculated location(s) and/or range(s) of object(s) in the sceneexternal to the taxiing aircraft.

A further embodiment of any of the foregoing systems, wherein thecockpit notification system can include an audible alarm that isactivated when the calculated location(s) and/or range(s) indicate oneor more of the object(s) in the scene has a combination of anlocation(s) and/or range(s) corresponding to a risk of collisionrelative to the taxiing aircraft.

A further embodiment of any of the foregoing systems, wherein thedigital processor can be further configured to determine pixelboundaries of the object(s) in the scene.

A further embodiment of any of the foregoing systems, wherein thedigital processor can be further configured to identify a fourth set ofpixel coordinates that lie within the determined pixel boundaries of theobject(s) in the scene external to the taxiing aircraft.

Some embodiments relate to a method for providing docking guidance to apilot of a taxiing aircraft. The method includes generating, by a cameramounted at a camera location on an aircraft, a two-dimensional image ofa scene external to the taxiing aircraft. The generated two-dimensionalimage includes pixel data generated by the two-dimensional array oflight-sensitive pixels. The method includes identifying first and secondsets of pixel coordinates within the image of the scene external to theaircraft. The identified first and second sets of pixel coordinatescorrespond to two vertically-separated and two laterally-separatedindicia, respectively, of an alignment fiducial indicating a parkinglocation for the aircraft. The method includes calculating, based atleast in part on the identified first pixel coordinates corresponding tothe two vertically-separated indicia, a range to the parking location.The method also includes generating a visual display of the image of thescene aligned with the optical axis of the camera. The visual display isannotated with the calculated range to the parking location.

The method of the preceding paragraph can optionally include,additionally and/or alternatively, any one or more of the followingfeatures, configurations and/or additional components:

A further embodiment of the foregoing method can further includecalculating, based at least in part on the identified second pixelcoordinates corresponding to the two laterally-separated indicia, anangle of the taxiing aircraft with respect to a normal vector of thealignment fiducial.

A further embodiment of any of the foregoing methods can further includecalculating, based at least in part on the identified second pixelcoordinates corresponding to the two laterally-separated indicia, alateral translation of the longitudinal axis of the taxiing aircraftwith respect to the parking location identified by the alignmentfiducial.

A further embodiment of any of the foregoing methods can further includeprojecting, from a projector location on the taxiing aircraft, light ofa spatial pattern onto the scene external to the aircraft, therebyilluminating a spatially-patterned portion of the scene.

A further embodiment of any of the foregoing methods can further includeidentifying a third set of pixel coordinates within the image of thescene external to the aircraft, the identified third set of pixelcoordinates corresponding to the spatially-patterned portion of thescene.

A further embodiment of any of the foregoing methods can further includecalculating, using triangulation based on the projector location of thelight projector, the camera location of the camera and the identifiedthird set of pixel coordinates, location(s) and/or range(s) of object(s)in the scene external to the aircraft from which the spatially-patternedlight projected by the light projector is reflected.

A further embodiment of any of the foregoing methods can further includegenerating a visual display of the image external to the taxiingaircraft, the visual display annotated with the calculated location(s)and/or range(s) of object(s) in the scene external to the aircraft.

A further embodiment of any of the foregoing methods can further includeactivating an audible alarm when the calculated location(s) and/orrange(s) of object(s) indicate one or more of the object(s) in the scenehas a combination of a location(s) and/or range(s) corresponding to arisk of collision relative to the taxiing aircraft.

A further embodiment of any of the foregoing methods can further includedetermining pixel boundaries of the object(s) in the scene.

A further embodiment of any of the foregoing methods can further includecalculating location(s) and/or range(s) of object(s) corresponding tothe determined pixel boundaries.

A further embodiment of any of the foregoing methods can further includeidentifying a fourth set of pixel coordinates that lie within thedetermined pixel boundaries of the object(s) in the scene but are notincluded in the identified third set of pixel coordinates.

While the invention has been described with reference to an exemplaryembodiment(s), it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment(s) disclosed, but that theinvention will include all embodiments falling within the scope of theappended claims.

The invention claimed is:
 1. A system for providing docking guidance toa pilot of a taxiing aircraft, the system comprising: a cameraconfigured for mounting at a camera location on the taxiing aircraft,the camera configured to generate a two-dimensional image of a sceneexternal to the taxiing aircraft, the generated two-dimensional imagecomprising pixel data generated by the two-dimensional array oflight-sensitive pixels; and a digital processor configured to identifyfirst and second sets of pixel coordinates within the generatedtwo-dimensional image of the scene external to the taxiing aircraft, theidentified first and second sets of pixel coordinates corresponding totwo vertically-separated and two laterally-separated indicia,respectively, of an alignment fiducial indicating a parking location forthe taxiing aircraft, the digital processor further configured tocalculate, based at least in part on the identified first pixelcoordinates corresponding to the two vertically-separated indicia, arange to the parking location indicated by the alignment fiducial. 2.The system of claim 1, further comprising a cockpit alarm and displaymodule configured to provide a visual display of the generated image ofthe scene aligned with the optical axis of the camera, the providedvisual display annotated with the calculated range to the parkinglocation.
 3. The system of claim 1, wherein the digital processor isfurther configured to calculate, based at least in part on theidentified second pixel coordinates corresponding to the twolaterally-separated indicia, an angle of the taxiing aircraft withrespect to a normal vector of the alignment fiducial.
 4. The system ofclaim 1, wherein the digital processor is further configured tocalculate, based at least in part on the identified second pixelcoordinates corresponding to the two laterally-separated indicia, alateral translation of the longitudinal axis of the taxiing aircraftwith respect to the parking location identified by the alignmentfiducial.
 5. The system of claim 1, further comprising: a lightprojector configured to be mounted at a projector location on thetaxiing aircraft and to project spatially-patterned light from the lightprojector onto the scene external to the taxiing aircraft, therebyproviding illumination of a spatially-patterned portion of the sceneexternal to the taxiing aircraft, wherein the digital processor isfurther configured to identify a third set of pixel coordinates withinthe image of the scene external to the taxiing aircraft, the identifiedthird set of pixel coordinates corresponding to the spatially-patternedportion of the scene, the digital processor further configured to usetriangulation, based on the projector location of the light projector,the camera location of the camera and the identified third set of pixelcoordinates, to calculate location(s) and/or range(s) of object(s) inthe scene external to the taxiing aircraft from which thespatially-patterned light projected by the light projector is reflected.6. The system of claim 5, wherein the spatially-patterned lightprojected by the light projector comprises infrared light.
 7. The systemof claim 6, wherein the camera is an infrared camera and thelight-sensitive pixels are sensitive to infrared light.
 8. The system ofclaim 5, further comprising a cockpit alarm and display moduleconfigured to generate a visual display of the image aligned with theoptical axis of the camera annotated with the calculated location(s)and/or range(s) of object(s) in the scene external to the taxiingaircraft.
 9. The system of claim 8, wherein the cockpit alarm anddisplay module includes an audible alarm that is activated when thecalculated location(s) and/or range(s) indicate one or more of theobject(s) in the scene has a combination of an location(s) and/orrange(s) corresponding to a risk of collision relative to the taxiingaircraft.
 10. The system of claim 5, wherein the digital processor isfurther configured to determine pixel boundaries of the object(s) in thescene.
 11. The system of claim 10, wherein the digital processor isfurther configured to identify a fourth set of pixel coordinates thatlie within the determined pixel boundaries of the object(s) in the sceneexternal to the taxiing aircraft.
 12. A method for providing dockingguidance to a pilot of a taxiing aircraft, the method comprising:generating, by a camera mounted at a camera location on an aircraft, atwo-dimensional image of a scene external to the taxiing aircraft, thegenerated two-dimensional image comprising pixel data generated by thetwo-dimensional array of light-sensitive pixels; identifying first andsecond sets of pixel coordinates within the image of the scene externalto the aircraft, the identified first and second sets of pixelcoordinates corresponding to two vertically-separated and twolaterally-separated indicia, respectively, of an alignment fiducialindicating a parking location for the aircraft; calculating, based atleast in part on the identified first pixel coordinates corresponding tothe two vertically-separated indicia, a range to the parking location;and generating a visual display of the image of the scene aligned withthe optical axis of the camera, the visual display annotated with thecalculated range to the parking location.
 13. The method of claim 12,further comprising: calculating, based at least in part on theidentified second pixel coordinates corresponding to the twolaterally-separated indicia, an angle of the taxiing aircraft withrespect to a normal vector of the alignment fiducial.
 14. The method ofclaim 13, further comprising: calculating, based at least in part on theidentified second pixel coordinates corresponding to the twolaterally-separated indicia, a lateral translation of the longitudinalaxis of the taxiing aircraft with respect to the parking locationidentified by the alignment fiducial.
 15. The method of claim 13,further comprising: projecting, from a projector location on the taxiingaircraft, light of a spatial pattern onto the scene external to theaircraft, thereby illuminating a spatially-patterned portion of thescene; identifying a third set of pixel coordinates within the image ofthe scene external to the aircraft, the identified third set of pixelcoordinates corresponding to the spatially-patterned portion of thescene; and calculating, using triangulation based on the projectorlocation of the light projector, the camera location of the camera andthe identified third set of pixel coordinates, location(s) and/orrange(s) of object(s) in the scene external to the aircraft from whichthe spatially-patterned light projected by the light projector isreflected.
 16. The method of claim 15, further comprising: generating avisual display of the image external to the taxiing aircraft, the visualdisplay annotated with the calculated location(s) and/or range(s) ofobject(s) in the scene external to the aircraft.
 17. The method of claim16, further comprising: activating an audible alarm when the calculatedlocation(s) and/or range(s) of object(s) indicate one or more of theobject(s) in the scene has a combination of a location(s) and/orrange(s) corresponding to a risk of collision relative to the taxiingaircraft.
 18. The method of claim 16, further comprising: determiningpixel boundaries of the object(s) in the scene.
 19. The method of claim18, further comprising: calculating location(s) and/or range(s) ofobject(s) corresponding to the determined pixel boundaries.
 20. Themethod of claim 18, further comprising: identifying a fourth set ofpixel coordinates that lie within the determined pixel boundaries of theobject(s) in the scene but are not included in the identified third setof pixel coordinates.